Name: joT67522 Date: 09/16/97


REPRODUCTION
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1) Create a subclass of Component which saves a data pointer to
   a PopupMenu, and which adds the PopupMenu to itself using the
   void add(PopupMenu) method in Component. Make the Component
   subclass implement Serializable.

2) Serialize the Component to a ObjectOutputStream.

3) Read the object back in from a ObjectInputStream.

4) The PopupMenu (which was serialized with the component because
   there was a non-transient pointer to it defined as a data
   member of the Component subclass) will have "lost" it's
   parent Component. Therefore, the menu will throw an exception
   when it's void show() method is called.

SAMPLE SOURCE CODE
------------------
// Package and import declarations
import java.util.*;
import java.io.*;
import java.lang.*;
import java.awt.*;
import java.awt.event.*;

public class TestComponent extends Container implements Serializable
{
    /**
    * Popup menu of Presentations
    */
    PopupMenu testMenu;

    /**
    * Empty constructor needed for serialization
    */
    public TestComponent()
    {
     // Call component constructor
     super();

        // Turn on mouse events for popup menus
        enableEvents(AWTEvent.MOUSE_EVENT_MASK);

     // Add presentation list items to a menu
     addMenuItems(menuItemList);
    }

    private void addMenuItems(Vector mi)
    {
     // Check if a menu is required
     if (mi.size() > 0)
     {
            MenuItem mi;

            if (testMenu == null)
            {
         testMenu = new PopupMenu();

         // Add a menu item for each item on the list
         for(int i = 0; i < menuItemList.size(); i++)
         {
         // Put title of Presentation into menu item.
                    // Use Presentation index as the value of the menu item.
         mi = (MenuItem) menuItemList.elementAt(i);
         testMenu.add(mi);
         }
         // Add the popup to the parent symbol
         add(testMenu);
            }
     }
    }

    /**
    * Processes mouse events and shows the test menu if the mouse
    * event is a popup trigger
    */
    public void processMouseEvent(MouseEvent evt)
    {
        if (evt.isPopupTrigger())
{
if (testMenu != null)
{
testMenu.show(this, evt.getX(), evt.getY());
}
}
    }
}
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